1. Field of the Invention
The present invention relates to a display device and display method suitably applied to, for example, a liquid crystal display, an organic EL (Electro-Luminance) display and the like, and particularly to a display technology capable of receiving light in parallel with emitting light.
2. Description of the Related Art
In related art, in the case where on a display screen of a display device such as a television receiver a touch panel capable of being operated when touching the screen is configured, the touch panel provided separately from the display device is superimposed on the display screen.
As a configuration that uses the touch panel separately provided, for example, there is the one in which a thin transparent input detecting device is attached on the screen. This is a touch sensor using a conductive film, and there are a pressure type that detects the pressure, a static capacity type whose static capacity is changed when a human body is touched and the like. Further, there is an electromagnetic induction type that uses a specific pen to input a position. Those types have a structure in which a specific position-detecting panel is superimposed on the surface of a display panel.
Although the above types that use the detecting panel superimposed on the display panel use a simple principle of detecting touch, the deterioration of the display quality occurs inevitably, because some material is superimposed on the display panel. Furthermore, since a method of mainly detecting the capacity change is employed, it is difficult to detect inputs to two or more positions simultaneously.
Also, as a method of a touch panel in which a panel is not attached to the surface, there is an optical type. In this touch panel method, light-emitting elements (light-emitting diodes) and phototransistors are combined and disposed on the left, right, top and bottom of a panel, and light is shielded by the finger and the like to detect the position. The deterioration of the display quality does not occur in this optical type, but a device installed in the surrounding area of the display device becomes large, which is not suitable for portable equipment.
Recently, in order to solve the inconvenience of those touch panels in related art, the one is proposed in which the screen itself of the display device functions as the touch panel without separately providing the touch panel. Patent document 1 discloses such display device that emits light and receives light in parallel.
In the display device that emits light and receives light in parallel, for example, the display (light-emitting) by an image display light-emitting element arranged on a display screen is performed intermittently, and electric charge corresponding to the received light is stored in the light-emitting element itself, and then the electric charge stored is read out. As a display device in which such configuration is possible, there is an organic EL display, for example. Furthermore, in the case where a display pixel does not have a function of receiving light (storing electric charge), such as an LCD (Liquid Crystal Display) device, it is proposed a structure in which a light-receiving element is disposed adjacently to the display pixel and the light is received by the light-receiving element during the pause of the display (light-emitting).    Patent document 1: Japanese Published Patent Application No. 2004-127272 (refer to FIG. 5)